Biosynthesis of platelet-activating factor (PAF-ACETHER). II. Involvement of phospholipase A2 in the formation of PAF-ACETHER and lyso-PAF-ACETHER from rabbit platelets.
The role of phospholipase A2 (PLA2) in the formation of platelet-activating factor (PAF-acether) by rabbit platelets is supported by several pieces of evidence. First, the release of PAF-acether was accompanied by that of its deacetylated analog, lyso-PAF-acether. Second, EDTA, EGTA, db-AMPc, p'-bromophenacylbromide and 874 CB, which, in spite of their structural diversity, are all PLA2 blockers, inhibited the release of both PAF-acether and of the lyso-compound. Third, addition of hog pancreas PLA2 to platelets as well as platelet lysis resulted in the release of lyso-PAF-acether, thus mimicking the metabolic events initiating formation of PAF-acether. These results indicate that PLA2 activation triggers both the second and the third pathway of platelet activation.
D000098:Acetophenones / Q000494:pharmacology; D000818:Animals; D001792:Blood Platelets / Q000378:metabolism*; D000001:Calcimycin / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D004533:Egtazic Acid / Q000494:pharmacology; D007700:Kinetics; D008244:Lysophosphatidylcholines / Q000096:biosynthesis* / Q000378:metabolism; D010740:Phospholipases / Q000494:pharmacology*; D010741:Phospholipases A / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D054467:Phospholipases A2; D010972:Platelet Activating Factor; D011817:Rabbits; D013917:Thrombin / Q000494:pharmacology
D000098:Acetophenones; D008244:Lysophosphatidylcholines; D010972:Platelet Activating Factor; D000001:Calcimycin; D004533:Egtazic Acid; D004492:Edetic Acid; D010740:Phospholipases; D010741:Phospholipases A; D054467:Phospholipases A2; D013917:Thrombin; C006821:4-bromophenacyl bromide